Steam generating system



May 30, 1939. A. cLARKsoN v S'iEAM GENERATING SYSTEM 2 Sheets-Sheet 1Filed Sept. 8, 1936 lbif 021 212,;

ATTORNEYS 1 May 30, 1939.

A. CLARKSON STEAM GENERATING sisq'su Fil d Sept a; 1956 '2 Sheets-Sheet2 INVENTOR.

' ATTORNEYS Patented May 30, 1939 UNITED STATES PATENT OFFICE 7 Claims.

This invention relates to a steam generating apparatus, usually of theautomatic or semi-automatic type. This apparatus is of high efllciencyin relation to its evaporative capacity, and

' is small in size, light in weight, easily controlled and capable ofbeing manufactured from ordinary commercialboiler material. Theinvention contemplates a generating apparatus in which the water isevaporated 'while passing through a coil or coils and, one of theobjects of the invention'is to so construct the apparatus'that the hotgases arefor'ced to pass through the apparatus in such manner as to heatthe coils most efliciently with a minimum destructive effect upon thecasing or other parts .ofthe furnace.

The principal object of the invention is to provide an improvedarrangement of the boiler coils, together with improved spacing andsupporting means forthese coils so as to retain the coils substantiallyin the desired position while permitting certain necessary expansive andcontractive movements.

Another object is toprovide a generator con.-

struction which permits a, maximum absorption" of both radiant andconduction heat in the water passing through the coil or coils.

A further object is to provide a steam generator having a generatingcoil or coils so constructed that the coil or coils may be considerablyoverheated without damage.

The generator according to the invention comprises a bank of connectedpipe coils positioned one within another about a common central axis andthe innermost coil enclosing a central heating space, the turns ofadjacent coils being 01fset so that the turns of one coil are staggeredwith respect to the turns of adjacent coils, in which a plurality ofseparate spacers are positioned at intervals between adjacent turns ofthe coils, certain of the spacers being attached to both of the pair ofturns and other spacers being attached to only one of the tums.'

One form of the invention is illustrated in the accompanying drawings inwhich:

Fig. 1 is a central vertical sectional view of the generator;

Fig. 2 is a detail plan vview of the outer generating coil;

view on line 33 of crating coil;

.ing apparatus herein disclosed and claimed.

type of combustion device. 10

The burner B, assuming that oil is to be used as a fuel, preferablycomprises an oil atomizer 30 projecting through a boss 3| on the top ofthe air duct l3. At 32 is'shown'an ignition device for Knitugthe oilspray from the atomizer.- 15 The oil is admitted to the atomizer througha. port controlled .by a diaphragm valve which opens only when a certainminimum fluid pressure is supplied. At lower pressures the valveautomatically closes. Arranged below the atomizer is a cylindricalstructure or-fire-pot 33 having an inturned curved lip 34 at its upperend. Thestructure 33 provides a combustion chamber arranged to providean air port 36 between it .and the combustion chamber and an air port 31between it andthe flame ring. Above the combustion chamber is a cone 38'formed with air openings 39. Another ring 40 is arranged above 30 theupper edge of cone'38 and is preferably pro vided with aninturned'flange 4|. This specific form of burner is merely shown by wayof example and it may be briefly stated that the air supply from duct l3flows in between the several members in such manner as to provide astabilized ignition zone within the rings 38 and 40, and air currentsare set upwithin fire-pot 33 so as to provide a substantially completecombustion, the hot products of combustion being discharged throughflame ring it into the central heating chamber surrounded by the pipeThe specific form of burner hereinabove described by way of example isdisclosed and 5 claimed in a division of the present application, saiddivisional case being filed under date of June 21, 1937, Serial No.149,466. It will be understood that other types of burner devices couldbe used with the improved steam generat- Preferably soot removers 42 arearranged between the inner and outer coils and are connected with acircular pipe 43 which receives steam, the soot removers consisting oftubular members perforated for ejection of steam between the turns ofthe generating coils. Steam is introduced into the circular pipe 43 atintervals or if and when the pipe coils become sufficiently sooted torequire it.

The steam is generated in a bank of connected coils positionedsymmetrically about a central vertical axis, the inner coils l5 and I6being preferably of larger pipe diameter than the outer coils ll, l8, l9and 20. This bank of coils, which for convenience will be designated asa whole by the letter K, is arranged between a body of refractorymaterial 2| at the end of the generator opposite burner B, the lower endas the apparatus is shown. and a body of refractory material 22 at theupper end of the structure which is arranged against a baille plate 23having a flared lip 23'. Metal seating members 24 and 25 are preferablyarranged respectively between the lower body of refractory material andthe bank of coils, and between the bank of coils at the top and therefractory body 22 and lip 23'.

The axial lengths of thecoils diminish from the inner coil to the outercoil, giving the bank of coils a double frusto-conical configuration.The space in the generator in which the bank of coils K is located, thatis, the space between the lower refractory material 2| and the upperrefractory material 22 is of similar configuration so that a taperedpassageway is provided for the furnace gases as they move from the innercoil to the outer coil and to the space 26 outside of the bank of coils,which space communicates with flue l2. As the gases cool and contract,they are brought into closer contact with the coils which increases theeiliciency of the apparatus, this efiiciency being further increased byhaving the outer coils of smaller pipe diameter than the inner coils.

The feed water is forced into the pipe coils through nipple 21 at theouter end of coil 20, and the steam and water mixture is discharged fromthe inner pipe coil l5 through a suitable connection not here shown.

Returning now to that portion of the generator which forms theparticular subject matter of this invention, the inner and outer sets ofcoils are of similar construction, except for the difierence in thenumber of coils or helices and the difference in pipe size. The coilsare not true helices but each consists of a plurality of circular loopsor turns, each turn being substantialily horizontal throughout nearly360 and connected with the next higher or lower turn by offsets 44.Outer coils l8 and H! are connected at one end of the bank of coils bythe offset 440 (see Fig. 2). Coils l9 and 20 and also coils I1 and i8are connected at the opposite end of the bank of coils by similaroffsets. Inner coils l5 and I6 are connected in a similar manner at oneend of the bank. Coils l6 and I! are joined by an outside connection.These end connections are so inclined that the turns of one coil arestaggered with relation to the turns of an adjacent coil of the bank.That is, the loops or turns of coil l6 are positioned opposite thespaces between the turns of coil l5, and so on. This staggeredrelationship of the loops or turns of the several coils existsthroughout substantially the entire 360 lengths of the turns. Thereforethe hot gases are forced to follow a sinuous path between the staggeredcoils and the gases are forced into intimate contact with a maximum ofthe pipe surfaces thus effecting a maximum heat exchange between thegases and 'the fluids in the coils.

The coils are separated and supported by sinuous spacers 45 to which,however, the coils are not attached. There may be any suitable number ofthese spacers. The sinuous spacers are flexible, and they allowexpansion and contraction of the coils while giving the coils thenecessary support one on the other.

There are also a plurality of separate spacers 46 and 5| positioned atsuitable intervals between adjacent or successive turns of the coils,certain of these spacers being attached to both of the pair of turnsbetween which the spacer is interposed, and other spacers being attachedto only one of these turns. In the example here shown, the spacers 46(Fig. 6) are arranged between the coils at substantially diametricallyopposed positions. These spacers 46 are welded or otherwise firmlysecured to the turns 41, 48 and 49, 50 between which they are disposed.The turns are thus rigidly tied together. at these points.

The spacers 5| (Fig. 7) are arranged between the turns at substantiallydiametrically opposed positions and at from the spacers 46. One of thesespacers 51 is welded to one of the turns between which it is interposed,for example, pipe 41, but is not-attached to the other pipe 48 of thepair. Similarly, a secondspacer is welded to pipe 49 but not to theother adjacent pipe 50.

Each of the spacers 46 and 5| is provided with a laterally extendingfinger portion which engages the pipe turn of a laterally adjacent coil.For example, the spacer 46 between turns 41 and 48 (Fig. 6) has a finger46' engaging the turn 49 positioned opposite the space between turns 41and 48.

It will be noted that the sinuous spacers 45 are used at suitablecircumferential intervals between the respective sets of spacers 46 and5|. The combination of the three sets of spacers 45, 46 and 5| givesadequate support to the elements of the bank of coils K in which thesteam is generated, as against distortion of permanent character, whilepermitting the movements of the coil elements (especially rotarymovement around the central axis) under temperature changes.

I claim:

1. In combination with a substantially helical steam generating pipecoil, a plurality of spacers between the turns of the coil which areattached to both turns, and a plurality of spacers between said turnswhich are attached to one turn only.

2. In combination with a substantially helical steam generating pipecoil, pairs of diametrically arranged spacers between the turns of thecoil which are attached-to both turns, and a plurality of diametricallyarranged spacers at 90 from the first mentioned spacers which areattached to one turn only of the turns which they space.

3. In combination with a substantially helical steam generating pipecoil, pairs of diametrically arranged spacers between the turns of thecoil which are attached to both turns, and a plurality of diametricallyarranged spacers at 90 from the first mentioned spacers which areattached to one turn only of the turns which they space; and means forsupporting the turns against movement in the direction of the axis ofthe coil while permitting circular movement of the coil.

4. A steam generator comprising a plurality of pipe coils centered abouta common central axis, the turns of which are offset so that the turnsof one coil are staggered with respect to the turns of adjacent coils,substantially diametrically arranged spacers positioned between eachpair of adjacent turns of a coil and attached to both turns, andsubstantially diametrically arranged spacers positioned between theseturns and arranged 90 from the first-mentioned spacers and attached toone of the turns but unattached to the other.

5. A steam generator comprising a plurality of pipe coils centered abouta common central axis, the turns of which are offset so that the turnsof one coil are staggered with respect to the turns of adjacent coils,substantially diametrically arranged spacers positioned between eachpair of adjacent turns of a coil and attached to both turns, andsubstantially diametrically arranged spacers positioned between theseturns and arranged 90 from the first-mentioned spacers and attached toone of the turns but unattached to the other, each of said spacershaving a laterally projecting finger engaging the turn of an adjacentcoil positioned opposite the space between the first mentioned pair ofturns.

6. A steam generator comprising a plurality of pipe coils centered abouta common central axis, the turns of which are oflset so that the turnsof one coil are staggered with respect to the turns of adjacent coils,and a plurality of separate spacing blocks positioned at intervalsbetween adjacent turns of a coil, each block between a pair of turnshaving a laterally projecting finger engaging the turn of an adjacentcoil positioned opposite the space between the pair of turns, eachspacing block being attached to one of the pair of turns.

7. A steam generator comprising a plurality of pipe coils centered abouta common central axis, the turns of which are ofiset so that the turnsof one coil are staggered with respect to the turns of adjacent coils,and a plurality of separate spacing blocks positioned at intervalsbetween adjacent turns of a coil, each block between a pair of turnshaving a laterally projecting finger engaging the turn of an adjacentcoil positioned opposite the space between the pair of turns,

certain of the blocks being attached to both of the pair of turns, andother blocks being attached to only one of these turns.

ALICK CLARKSON.

